/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.log4j.spi;

import org.apache.log4j.*;
import java.util.Enumeration;

/**
A <code>LoggerRepository</code> is used to create and retrieve
<code>Loggers</code>. The relation between loggers in a repository
depends on the repository but typically loggers are arranged in a
named hierarchy.

<p>In addition to the creational methods, a
<code>LoggerRepository</code> can be queried for existing loggers,
can act as a point of registry for events related to loggers.

@author Ceki G&uuml;lc&uuml;
@since 1.2 */
public interface LoggerRepository {

    /**
    Add a {@link HierarchyEventListener} event to the repository.
     */
    public void addHierarchyEventListener(HierarchyEventListener listener);

    /**
    Returns whether this repository is disabled for a given
    level. The answer depends on the repository threshold and the
    <code>level</code> parameter. See also {@link #setThreshold}
    method.  */
    boolean isDisabled(int level);

    /**
    Set the repository-wide threshold. All logging requests below the
    threshold are immediately dropped. By default, the threshold is
    set to <code>Level.ALL</code> which has the lowest possible rank.  */
    public void setThreshold(Level level);

    /**
    Another form of {@link #setThreshold(Level)} accepting a string
    parameter instead of a <code>Level</code>. */
    public void setThreshold(String val);

    public void emitNoAppenderWarning(Category cat);

    /**
    Get the repository-wide threshold. See {@link
    #setThreshold(Level)} for an explanation. */
    public Level getThreshold();

    public Logger getLogger(String name);

    public Logger getLogger(String name, LoggerFactory factory);

    public Logger getRootLogger();

    public abstract Logger exists(String name);

    public abstract void shutdown();

    public Enumeration getCurrentLoggers();

    /**
    Deprecated. Please use {@link #getCurrentLoggers} instead.  */
    public Enumeration getCurrentCategories();

    public abstract void fireAddAppenderEvent(Category logger, Appender appender);

    public abstract void resetConfiguration();
}
